1. Field of the Invention
The present invention relates to a driving device that uses an electromechanical transducer as a driving source.
2. Description of the Related Art
As a technique of this field, Japanese Unexamined Patent Application Publication No. 7-274544 discloses a driving device that includes a driving shaft (non-deforming portion) fixed to one end of a piezoelectric element, and a lens barrel (driven portion) frictionally engaged with the driving shaft by a pressure spring (friction portion) and a friction plate. When pulsed voltage is applied to the piezoelectric element, the piezoelectric element expands and contracts, and the driving shaft is displaced, thus moving the lens barrel frictionally engaged with the driving shaft.
However, in the above-described driving device as the related art, the pressure spring and the friction plate are fixed to the lens barrel, and therefore, vibration resulting from friction caused between the pressure spring and the friction plate, and the lens barrel is directly transmitted to the lens barrel. This vibration due to friction has a great influence on the lens barrel, and causes deviation of the optical axis.